Institut des Sciences Moléculaires d'Orsay



jeudi 26 novembre

Mise à jour
jeudi 26 novembre

Accueil > Équipes scientifiques > Surfaces, Interfaces, Molecules & 2D Materials (SIM2D) > Chimie de surface & électrons lents, 0-50 eV > Low-energy electron irradiation of self-assembled monolayers (SAMs)

Low-energy electron irradiation of self-assembled monolayers (SAMs)

par Amiaud Lionel - 17 juillet 2015

In biosensors, SAMs serve as canvases of chemical functions organized on a surface. Electron irradiation can be performed to modify localized sections of these monolayers. Conventional irradiation techniques used in surface modification employ high-energy radiation in the form of X-rays and high energy electrons which have poor control over the changes induced on the surfaces. In fact, the chemical modifications observed on surfaces bombarded with high-energy radiation are mostly due to the concomitant release of low-energy secondary electrons that interact with the molecules on the surface. Several processes could result from these interactions depending on the energy of the secondary electrons. Careful control of these processes can be done by determining the precise electron energies that induce chemical modifications on the SAMs. We therefore study the nature and mechanisms of these chemical modifications and determine electron energy ranges at which these processes could occur.

SAMs that have been extensively studied by the group include 11-mercaptoundecanoic acid (MUA) and p-terphenylthiol (TPT) chemisorbed on gold substrates. As shown in the illustration, the team was able to determine a resonant process at 6 eV for the low-energy electron irradiation of TPT leading to a loss of aromaticity via cross-linking of the aromatic segments. (PCCP 16(2014) 1050)

Main Collaborators :

Related Publications
- Selective terminal function modification of SAMs driven by low-energy electrons (0-15 eV).
Houplin J., Amiaud L., Humblot V., Martin I., Matar E., Azria R., Pradier C.M., Lafosse A.
PCCP 15 (2013) 7220
- Low-energy electron induced resonant loss of aromaticity : consequences on cross-linking in terphenylthiol SAMs.
Amiaud L., Houplin J., Bourdier M., Humblot V., Azria R., Pradier C. - M. & Lafosse A. PCCP 16(2014) 1050